But it wasn't filed before ones like these... ;) http://www.google.com/patents?id=NLxRAAAAEBAJ&printsec=drawing&...http://www.google.com/patents?id=T5JFAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=falsehttp://www.google.com/patents?id=3G1IAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=falsehttp://www.google.com/patents?id=vvF4AAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=false